Answer:
the first term is a1
the distance between the numbers is d
we have:
a5 = a1 + 4d = 23
a12 = a1 + 11d = 72
so we have the equation:
a1 + 4d = 23
a1 + 11d = 72
=> a1 = -5
d = 7
=> an = -5 + 7(n - 1) = 7n - 12
with an = 7n - 12
=> a2 = 2
a3 = 9
so the first three terms is -5; 2; 9
12:00-9:30 = 2:30
12:30+8:30 = 8:30
2:30 + 8:30 = 11:00
11 total hours elapsed
C. they are worth the same amount of money, 1/2 and 2/4 are both 50% or 50 cents
Answer:
Step-by-step explanation:
the probability that at least one envelope is a yellow envelope is 16/21
Step-by-step explanation:
The probability that at least one envelope is a yellow envelope is P(Y);
P(Y) = 1 - P(Y)'
P(Y)' is the probability that no envelope is a yellow envelope.
Given;
red envelope = 1
blue envelopes = 3
green envelopes = 2
yellow envelopes = 3
Total = 9
Number of non-yellow envelope = 9 -3 = 6(6 envelope are not yellow)
P(Y)' = P1 × P2 × P3
there is no replacement;
P(Y)' = 6/9 × 5/8 × 4/7
P(Y)' = 5/21
From equation 1;
P(Y) = 1 - 5/21
P(Y) = 16/21
the probability that at least one envelope is a yellow envelope is 16/21.
